Inking pad in hand-held self-inking stamps

ABSTRACT

The top surface of an inking pad is formed by a nonwoven fabric comprising cotton fibers bonded by a natural or nitrile rubber latex.

United States Patent Rudolf Feb. 15, 1972 [54] INKING PAD 1N HAND-HELD SELF- INKING STAMPS [56] References Cited [72] Inventor: lleribert Rudolf, Wels, Austria UNITED STATES PATENTS 1 Assisnw 81 5911119 Trodai-werkm Wels, 1,518,756 12/1924 Rapley et a1. ..1 18/264 Ausma 1,605,899 11/1926 Moses ....161/244 1221 Filed: Jan. 30, 1969 2,155,441 4/1939 Osborne ....161/244 x 2,978,785 4/1961 Wenzell et a1. ..161/249 X [21] App1.No.: 798,856

Primary Examiner-Harold Ansher [30] Foreign Application Priority Data Assistant Examiner-C. B. Cosby Mar. 5, 1968 Austria ..A 2123/68 Kenna 52 us. (:1. ..1o1/333,161/146, 161/170, [57], ABSTRACT 161/251, 161/2 161/256, 1 The top surface of an inking pad is formed by a nonwoven 1 1!!!- Cl 5 1332b 341k fabric comprising cotton fibers bonded by a natural or nitrile [58] FieldolSearch ..161/267, 244, 249, 251, 256, mbbetlatex,

3 Claims, 1 Drawing Figure INKING PAD lN HAND-HELD SELFJNKING STAMPS This invention relates to an inking pad in hand-held self-inking stamps, inking rollers or the like.

The usual inking pads consist of felt and have a covering of woven fabric. lnking pads consisting of foam rubber with or without a covering of woven fabric, or with a knit fabric of rayon, which is bonded to the foam rubber by vulcanization, are known too. None of these inking pads is fully satisfactory. A covering of woven or knit fabric always involves the disadvantage that the pattern of the woven or knit fabric appears in the impression after a certain time of use, particularly when the stamp impressions are relatively large.

lnking pads in self-inking hand-held stamps must meet particularly high requirements becausethe inking pad must be perfectly flat, strong, yet resilient, and must have a highly wear-resisting surface. lt must have a large storage capacity for the ink and possess an extremely high capillarity to ensure a fast followup flow of the ink, particularly in a lateral direction because, in self-inking stamps, the ink is always removed from one and the same area of the pad. None of the known ink carriers has such storage capacity and such capillarity and their surface also lacks the required wear resistance.

It is an object of the invention to provide an inking pad which meets all these requirements so that it is particularly suitable for self-inking stamps.

According to the invention, at least the uppermost layer of the inking pad consists of a nonwoven cellulosic fabric of cotton or a mixture of cotton and fibers of regenerated cellulose or cellulose acetate, and is bonded with natural rubber latex or nitrile rubber latex, which latex may be mixed with a dispersion of synthetic resin. Such nonwoven fabrics are already used on a large scale as towels or wiping cloths or the like and are distinguished by a high absorption capacity for liquid and an extremely high capillarity. Besides, they have a highly wear-resisting surface. Tests have shown that the surface of such nonwoven fabric will not be damaged after a use in which a covering of woven fabric has been completely worn under the same conditions. The excellent capillarity in the direction at right angles to the surface is apparent from the fact that the inking power has not decreased after thousands of impressions have been taken from the same area. When the inking pad according to the invention has become dry after some time because much ink has been taken, it can be re-inked without difficulty. The ink which is applied in drops is absorbed within seconds and automatically assumes an even distribution. Obviously thereis no danger of an appearance of a pattern in the impression after some time.

When a thicker inking pad is desired, the nonwoven fabric may be laminated or adhered to a backing consisting of a mixed felt, wool felt or needle-punched felt. The adhesive between the two layers preferably has a netlike pattern so that the bond does not eliminate the capillary connections between the felt and the nonwoven fabric. The layers may be bonded together, e.g., with polyvinyl acetate or its copolymers, under the action of pressure and heat in the presence of moisture. Alternatively, the nonwoven fabric may be bonded to the felt in a dot pattern by the application of a suitable powdered synthetic resin, which is suitably distributed, followed by a heat treatment under the action of pressure.

The drawing is a perspective view showing an inking pad according to the invention for use with hand-held self-inking stamps.

The inking pad consists of an uppermost inking pad layer 1 and a backing 2. These two layers are joined by an adhesive layer 3. The inking pad layer 1 consists of a nonwoven fabric of cotton or the like bonded by nitrile rubber latex or the like. The backing 2 consists of a mixed felt.

What is claimed is:

1. ln combination with a hand-held self-inking stamp, an inking pad for transferring ink to the stamp, the inking pad having a top surface for direct contact with the stamp and consisting of a nonwoven fabric comprising cotton fibers bonded together by a natural or nitrile rubber latex, a backing layer laminated to the nonwove n fabric, and an adhesive layer of a netlike pattern intermediate the nonwoven fabric and the backing layer for bonding the same to each other.

2. In the combination of claim 1, wherein the fabric comprises additional cellulosic fibers selected from the group of regenerated cellulose and cellulose acetate fibers.

3. in the combination of claim 1, said backing layer being of felt. 

2. In the combination of claim 1, wherein the fabric comprises additional cellulosic fibers selected from the group of regenerated cellulose and cellulose acetate fibers.
 3. In the combination of claim 1, said backing layer being of felt. 